From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 7F43D3858D28; Mon, 4 Mar 2024 15:10:54 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 7F43D3858D28 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1709565054; bh=kvgONSSghzyFPI9AYzV9zRrmMXg8S2c19XsRGuMgdfA=; h=From:To:Subject:Date:In-Reply-To:References:From; b=fnIsEfpCKVRj76cWWbzlhxng05gWIj2g11Pm3Z9RE6oLHj/R/WPlCGdbtYzcwqRiY VkygWkXBhRYJSAv6G5KeKgOAr7Woiz+hNX/r87qKZy4YyfDbS2FobVpN6RttG8/XOD 8nwIif5knwblf0hEkL4crfqhBJhDt2XNSv0hnuAA= From: "rguenth at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/113441] [14 Regression] Fail to fold the last element with multiple loop since g:2efe3a7de0107618397264017fb045f237764cc7 Date: Mon, 04 Mar 2024 15:10:54 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: tree-optimization X-Bugzilla-Version: 14.0 X-Bugzilla-Keywords: missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: rguenth at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: 14.0 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113441 --- Comment #40 from Richard Biener --- So I wonder if we can use "local costing" to decide a gather is always OK compared to the alternative with peeling for gaps. On x86 gather tends to be slow compared to open-coding it. In the future we might want to explore whether we can re-do costing for alternatives without re-running all of the analysis at least for decisions we know have only "local" effect.=